Hebbebt hatjsbath



"RUSS RH tRtNCE EXAMINLK March 8, 1932. H HAUSRATH ET AL 1,848,882

pxc-m" ELECTRIC REGULA'IING DEVICE V Filed Feb. 7, 1928 2 Sneets-Sheet 1I l i l l i 8 I l I I I 25 U Z0 3 ckoss REFERENCE I MINER March 8, 1932.H. HAUSRATH ET AL 1,848,882

LIGHT ELECTRIC REGULATING DEVICE Filed Feb. 7; 1928 2 Sheets-Sheei 2Patented Mar. 8, 1932 UNITED STATES PATENT OFFICE HEB-BERT HAUSRA'I'E,0F DUB-LACK, nan. ram-sauna, AID mum OI KEEL, GERMANY, 'ASSIGNORS 130 mm maul-m em nn'rnmns- GESELLSOHAITK.B.H.,QFKIEL,GM

LIGlE'I mare BEGULATIIIG DEVICE Application fled Iebruar'y 7, 1838,Serial Io. 858,084, and in Germany Il'ebn'ary 10, 1887.'

The invention refers to such devices which are suitable for indicating achange in observable conditions which themselves, however,

Fig. 1" represents a side elevation of reflector 2 55 and mirror 33 inFig. 1.

Fig. 2 represents a further modified form,

do not bring about changes in the conditions. and

6 Such devices are for instance sensitive electric measuringinstruments, such as, mirror galvanometers, furthermore pyrometers,thermometers, barometers and others. They may also, as it often occursin the chemical industry, consist of a transparent tube, through which agas or a liquid is led, the transparency of which is a criterion for itscomposition or its state.

In all such devices the service conditions 15 are read off on the deviceitself by the operating stafi. Then further action is required by theoperating stafl, namely to apply the results of the reading to theregulation of the service condition or to transmit the readings to moredistant places.

The present invention proposes to dispense with the intermediary of the0 rating stafi for the above-named purposes y providing a contrivancefor either regulating the working conditions in accordance with newlychanged conditions or capable of transmitting the position of theindicating devices to a distant point if that is required in aparticular system.

In order to carry out the idea underlying the present invention, aphoto-electric cell is utilized. The intensity of the li ht beam fallinon such a cell is controlled y the device to observed. Over suitablerelay arrangements it releases mechanical forces for regulating amovable element according to the movements of the device to be observed.By this movable element the working condition can then either bedirectly regulated in the required manner or the transmitter of a longdistance indicating device can be actuated, the receiver of whichpermits the perception of the working condition at any distant place.

.A reduction to practice of the invention is represented in theaccompanying drawings in which:

Fig. 1 represents a diagrammatic lay-out of I the system. odified f ig.1 represents a m portion 0 Fig. 2" represents a modified form of re 55fiector 35 used in the modification Fig. 2.

In Fig. 1 a photoelectric cell is shown at-l, 2 and 3 are two criticalvoltage tubes, 4 is a condenser, 6 a relay and 7 a transformer.

By critical voltage tubes we mean any type d0- of evacuated tube havingat least two elec trodes, which tube by virtue of its constructionfirmits a uni-directional discharge only at or yond a critical voltage.Among these tubes may be mentioned for instance cold 6 glow cathodetubes, such as are known in the trade under the name Badiotron model UX-874, but we do not desire to limit the present arrangement to this typeof tube. Any tube,

having two or more electrodes and having 10 either a cold glow cathodeor a heated cathode, which neduces the resistance of the path betweenthe cathode and anode upon the application of a voltage of, or beyond, acritical value for the particular tube and its circuit 1 connection maybe employed. 8 is a current source feeding the whole circuitarrangement, 9 is a contact controlled by the relay 6, 10 is a doublerelay with two windings 11 and 12, the armature 13 of this relayregulating a an coupling wheel 14 splined on a shaft 15, on which' itcan be shifted in axial direction. A hand 16 is fastened to the shaft15, moving over a scale 17 and furthermore a transmitter 18 of any longdistance indicating sys- 85 tem is mounted on shaft 15. Finally theshaft 15 carriesfixedtoita inion 19 meshing witharack20. Thisraoperatesatranslucent wedge 22 mounted on a slide 21, this wedgeconsisting of a material uniformly per- .0 vious to light, so that, onaccount of the Q wedge-shape of this body. its perviousness variesproportionately to its movement in longitudinal direction.

23 is a double relaysimilartorelay 10. It .5 has two windings24 and 25.Its armature27 pivoted at 26, carries a source of light 28 at itsextremity. At the pivotal end of the armature a contact spring 29 isprovided which iSconnededtothecurrentsonrceSand,

whose cylindrical axis coincides with the ro-.

tary axis of shaft 32, so that a beam of light thrown from lens 42 inthe direction of shaft 32 is reflected by way of mirror 33 ontoreflector 35 and re-reflected b it and by way of mirror 34 in theoriginal irection as shown by the dash line. It will thus be understoodthat when the shaft 32 of the measuring instrument rotates as a functionof the measuring instrument, the reflected light beam will sweep overthe curvature of reflector 35, stopping in accordance with theindicating position in which shaft 32 has come to rest. In other words,for' instance point a on the reflector 35, Fig. 1", at which the beamhas come to rest is a measure for the indicating posltion whichinstrument shaft 32 has assumed.

Owin to the structural relation of the elements escribed the light beamin leaving mirror 34 maintains the original axis in which it is suppliedfrom lens 42, no matter at which point shaft 32 has come to rest,respectively no matter where the reflection point a is lo-' cated on thereflector 35. This reflector has a continuously increasing lightreflecting power, which is indicated in Fig. l" by the curved arrow, sothat the further point a is located in the direction of this arrow themore light of the original beam will be reflected onto mirror'34 andemanate from the latter. A reflector with such varying light reflectingpower can be made for instance by polishing successive surface portionsbetween its two ends from a rough, non-reflecting condition at one endto a higher and higher degree, until a highly reflectin condition exlateat or near the other end. n other words, the several surface portionsbetween its ends are imparted with successively different lightabsorbing properties, varying from substantially full absorption tosubstantially full reflection of the light 36 and 37 are two gear wheelsrotating continuously in opposite direction. They are continuouslydriven by any suitable source of power for instance an electric motornot shown.

88 is a relay with retarded action (due to dash p'ot 38), the armature39 of which relay closes the two contacts 40 and 41 in deenergiaedcondition. 42 and 43 are two optical lenssystems suitably designed toact as condensers for the light emanating from the as follows: Let itbe, assumed that measurmg instrument shaft 32 has assumed a certamindicating position, so that in case ali t beam is thrown from lens 42towards ce 1 it is reflected by reflector 35 at the Qint a of itssurface F' 1'). Let it be rther assumed that t e amp 28 has justoccupied the position shown in full lines. The li ht beam emanating fromthe lamp now fa throu h the translucent wedge 22 onto, the hoto-e ectriccell. Consequently, a current ows from battery 8 over the cell,condenser 4, left coil of transformer 7, contacts 41, 40 now closed,back to battery 8, thereby gradually charging the condenser 4. As soonas, the condenser 4 is sufliciently charged and has reached the criticalvoltage for tube 2, it discharges by way of this tube. This dischargecurrent rush flows through the primary windings p of the transformer 7and a corresponding. current is induced in the secondary windings a.This current is directed the same as that delivered by battery 8, itsvoltage being thus added to that of batte 8, the combined voltages beingstro enoug to send a current through valve 3 an through rela 6, whichattracts its armature 6", thereby c osm contact 9. This permits acurrent to flow cm the battery 8 over the contact 9, through the coil ofretarded relay 38, coil 12 of relay 10, coil 25 of relay 23,

contact 30 and contact spring 29 back to battery 8. The armature 13 ofrelay 10 is drawn down by the core end which carries coil 12 andconsequently the gear wheels 14 and 36 are thrown out of mesh and gearwheels 14 and 37 brought into mesh. Over' the drive 19 and 20 thetranslucent wedge 22 commences travelling to the left and consequentlythe li ht beam intensity from lamp 28 through we 22 and thus its actionupon the photo cell 1 is decreased. Simultaneously with the movement ofthe relay armature 13, the relay armature 27 of relay 23 has alsoaltered its position and has been thrown over into its left handposition shown in dotted lines. Consequently, the light beam now strikesthe photo-electric cell 1 thro h condenser lens 42 over mirror 33, assumpoint a of reflector '35 (Fig. 1) and mirror 34.

At the same time the contact :pring 29 now made contact at 31. In ameantime the retarded armature 39 of relay 38 acts and breaks theconnection between the two contacts 40 and 41, so that the current frombattery 8 through critical voltage tube 3-is interrupted. nsequentlyrelay 6 is de-energized and contact 9 controlled by it is opened.

Translucent edge 22 continues being displaced towards the left asdescribed. before 7 until the condenser 4 is again sufliciently chargedover the cell 1, to discharge over tube 2. Now the occurrences alreadydescribed above with respect to transformer 7 and tube 3 are repeatedwith the difl'erence, however, that now the winding 11 of relay 10 andwinding 24 of relay 23 are energized, so that gear wheel 14 is shiftedout of mesh with wheel 37 and back into mesh with wheel 36 and the relayarmature 27 with its lamp 28 is thrown back into its right hand positionsending the light beam a ain throu h wedge 22, which is now trave ing to-t e right. These occurrences are continually repeated and result in anadjustment of the translucent wedge 22 into a position in which, whentraversed by a beam of light from lamp 28, it has the same lightabsorption as the point a of reflector 35.

If the light absorption of the point a of the reflector struck by thelight beam is less than that of the part of wedge 22, traversed at theprevailing wedge adjustment,

that a ference will remain by which the wedge has '22 in bothdirections'can be re 'on scale 17, hand 16 moved further to the right.If, however, the light absorption of the point a of the reflector 35 andof the portion of wedge 22 traversed by the lightbeam are of the samevalue, the movement amplitudes of the wedge in both directions are thesame, so that the wedge 22 reciprocates about a central position whichis a measure for the position of the mirrors '33 and 34 with respect tothe arc of reflector 35 over which they sweep. The degree of uniformityof the motion amplitude of wedge 'ly read off volves with shaft 15.

In the arrangement shown as example in Fig. 1 the light absorption ofthe different ticular portions of the wedge Eomts on reflector 35 ontowhich the beam as been thrown by the mirrors 33 .and 34 is compared withthe light absrption of parthe wedge is displaced until the portions ofequal absorption are found.- A similar arrangement can be applied incases where the perviousness of gases or liquids forms a measare fortheir condition. In such cases the mirrors 33 and 34'a'nd reflector 35are re- .tube 49 through which the light beam can pass placed by a tube46 shown in Fig. 1. This is closed at both ends by glass plates in thedirection 32 (Fig. 1), and laterally inlet 47 and outlet 48 are providedby which .the -fluid under investigation is forced through tube 46. 'Thetranslucent wedge 22 is here shifted back and forth in the mannerrespectively described, until its light absorption correspends with theabsorption of the li ht by t e' fluid to be tested. Consequently, eposition of the wedge forms a measure for the perviousnessof the mediumto be tested and this wedge position can, therefore, be locally read at17 or be transmitted to any distant glint -for observation by anysuitable means own in the art, or the different wedge position may beemployed for theregulatlon of a working occurrence concerning the fluid.

Another form of reduction of this invention to practice is representedin Fig. 2. In this figure an partsshown correspond to Fig. 1withtheexception 'of the following modification:

The displaceable translucent wedge 22 has been dispensed with. vIn itsplace afixed body 44 of constant light absorbing capacity issubstituted. .The reflector 35 with its increasing light reflectingsurface is no longer fixed like in Fig. 1, but pivotally arranged torotate about the rotation axis of instrument shaft 32, and it isdirectly geared to the driving wheel 19 by the extended rack 20 which inFig. 1 operates wedge 22. The thus modified arrangement works asfollows:

Similarly to the modification shown in Fig. 1 the photo-electric cell 1is alternatively illuminated over the reflector 35 and the comparisonbody 44. Consequently, the reflector 35 makes reciprocating movementslike wedge 22 in Fig. 1. As the perviousness of the part 44 isinvariable, the reflector 35 is ad 'usted by the gearing described sothat the re ecting point a (Fig. 1") for the light beam is finallylocated at a point of the re flector 35 which has the same lightabsorption as body 44. If theinstrument shaft 32 with mirrors 33 and 34should move into another position, thereby moving the reflecting pointof the beam to another position on reflector 35, the reflector willfollow until it has brought the aforementioned point of similar lightabsorption to the .newly adjusted reflecting point. Thus the position ofreflector 35 becomes a measure for the positions of instrument shaft 32,which positions may be read of on scale 17 or transmitted to distantpoints by any suitable means known in the art. Otherwise the function ofthe whole arrangement is exactly the same as that according to Fig. 1.It represents merely a simplification inasmuch as no longer twobodies ofdecreasing absorption power, but only one is necessary.

This remaining body of continually in.

creasing absorbing power represented in Fi 2 by reflector 35 can also bedispensed withm this arrangement. ifthe cylinder surface of reflector 35is made of two parts, one of which has an absorbing power of nearlynought, while the absorbing power of the other art is practically totalthe meeting, line of th parts being parallel to the axis of rotation ofresult ofs'aidvariable.

shaft 82, respectivel of reflector 85. This reflector form is indicatedin Fig. 2, where for instance 35 may indicate the hly refleeting rtionand-35" the practic y totally absor ing portion. The meeting line isrndrcatedat 85'. this opegfiontfif tlie arrangement previo y escrr wi reerencetoF' .2,thismodifiedreflectorisfinally adj in F 2 by theregulating de- 10 vicesothatthelig tbeamisthrownjuston the line 85between both reflector parts 85 and 85'. According to whether thecomparison body 44; absorbs more or less 'light,thetbeamwillenclosethegreater vol of the light i r. e arrangement,therefore, makes pou i 1c the substitution of the reflector 2' for thereflector 85 of continually varia le absorbing power shown in Fig. 2which is relatively dlficult to construct, and permits the ration with acombination of reflecting an dimmed sur- In the constructive examplesonly some characteristic forms of the practical application of theinvention are represented. Naturally the individual operatrng elementsof the ant, merely shown'as examples, may easily be replaced I by wellhnownfiuivalents. For instance, the

twoelectrode ves2and8connectedincascadema berelacedbythreeelectrode.valves. the ttercasethevoltagea pliedtothegridelectrodeofathreeelectrode valvecanbevariedbythecurrent Y through-the photo electriccelluntil'thevalve acts. usingvalvesofthist ,advantage may also be taken of theirvior when usednearflrebendintheircharacteristic tho |:'.u".| .h formagma thereflectormFig.2mayberep byany other a I 'valent gearing whichproduces the li iln th a once rm catmg evarymg conditions .of a variableelement, comprising a beam source of light, a'photo-electr'ic l.dispoeedto-encounter said beam, a reflector having a cylindrical surfaeeof d talno 'ualities "vendrs P In a device for indicating the varyingrectim, a mirror for refl the 1.3: t beam from sa1d;s'ounce by way 0said u toeaidcelbsaidmirror'systembefixedtoaaidvanableelementtovarythepoint upon said riflector therebyg bso eluding said cell, a currentaource critical voltage tubs and current 0 means actuated in accordancewith intensifies of the beam saidmd a tranducant wedge having desorption than that of. said to 4 varying creasing light absorbing powerin the direc- I tion of its inclination, means controlled by saidcurrent 0 rated means for alternatel direct said ht beam to the cellthrong said w and y way of said reflector, reversible gearing controlledby said current operated means for shifting said wedge to decrease orincrease the light intensity of the beam directed through the wedge uponsaid cell in accordance. with the decreased or increased beam intensitydirected by way of the reflector upon said cell to equalize the lightintensities of the alternately beams, and means for indicating the wpositions, to indicate the extent to which sa1d variable element hasvaried;

2. In a device for indicating the varying conditions of a variableelement, compr sgrfi a beam source of light, a photo-electric disposedto, encounter said beam, a reflector a cylindrical surface of decreasingt a tion, a mirror system for reflecting the ht beam from said source byway of said ecftosaidcelhsaidmirrorsystembein fixed to said variableelement to vary the acting point upon said reflector, thereby strikingreflect points of varying light absorption in acco cewith the variations"of said variable element, control circuits including said celk acurrent source, critical voltage tubes an current operated meansactuated in accordance with the varying intensities of the beam strikingsaid cell and a translucent body and means controlled by said currentoperated means for alternatel directing said light beam to said cellthroug said body and rption qualities along a given direcby .wa of saidreflector, reversible gearing contro ed by said current operated meansfor moving said reflector from its revious position to decrease orincrease the 'ght intensity of the beam reflected by it according its towhether the reflecting epoint was previously ement to a int on ter hghtabequalize the beam absorption by the reflector and said moved by saidvariable the reflector of smaller or body'and the beam action u n thecell, and

means for indicating the fierent reflector positions to indicate theextent to which said variable element has varied from a previous ition.

beam in accordance with its own variations,

control circuits including said cell, a current source, critical voltagetubes and current operated means actuated in accordance with theintensities of the light striking the cell, and additional movable meansfor said beam, controlled by said current op- 4 'erated means, andhaving means for varying 21 1?;m i2i bem$ti v t in es 0 e sai ce andmeans connected with said addie tional guidmg means for indicating theextent to which said variable eleme has varied.

. 4. In a device for indicating e varying conditions of a variableelement, comprising a beam source of light, a photo-electric cell 0 andmeans for guiding said beam onto said cell, means controlled by saidvariable element for varying the intensity of the light guided onto saicell, a second means. for guiding a beam from said source to said cell15 and having means for varying the intensi of the light soguided,control circuits inclu ingessa'id cell, a current source, criticalvoltage tu and current operated means for actuating one of said guidingmeans to vary its posi- 90 tion with respect to the light beam inaccordance with the light response of said cell, to adjust said actuatedguiding means into a position correspondin with the varied condition ofsaid variab e element, and means 25 for indicatin the adjusted positionof said actuated gui ing means. a

- 5. In a device for indicating the varying conditions of avariableelement, comprising a beam source of light, a photo-electriccell and 30 a reflector servin as a guidin element for said beam to saicell, said re ector having different light absorption qualities ondiflerent portions of its surface, a mirror system for reflecting thebeam from said source by .Way of said reflector to said cell, saidmirror system being fixed to said variable element to direct the lightto different parts of said reflector in accordance with the differentpositions .which said variable element assumes, a second, translucentguiding element for said beam to said cell, for varying the intensity ofthe light so guided, control circuits inclu in said cell, a currentsource, critical olta e tu es and current operated means ac uated 1naccordance with the varyin intensitiesof the light reflected upon saidce one of said guiding elements being movable and controlled by saidcurrent operated means'to vary its position with respect to thelight-beam in accordance with said'varyin hght intensi- -ties, producedby the reflected light striking different portions of diflerentabsorption qualities on said reflector, said movable guiding elementhaving indicating means to give an indication of the extent to whichsaid variable element has varied.

In testimony whereof we aflix our signatures. HERBERT HAUSRATH. HERMANN-SAAOKE.

